1. Technical Field of the Invention
The present invention relates in general to the field of telecommunications, and in particular, to relocating a beacon in a wireless communications system such that mobile terminals know where to find it.
2. Description of Related Art
Wireless communication systems provide many benefits to both subscribers and network providers. Subscribers enjoy increased safety, convenience, and productivity while wireless network providers are able to provide telephone service with only incremental capital investments. Incremental capital investments are possible because some of today's modern wireless systems enable providers to easily add base stations, and thus capacity, as subscribers request additional service.
Some of these modern wireless systems operate in unlicensed portions of the electromagnetic spectrum. When operating a wireless system at shared unlicensed frequencies, certain Federal Communications Commission (FCC) regulations apply to system information broadcast channels. For example, FCC Rule 15.323 (c)(4) prohibits channels used exclusively for control and signaling information from transmitting continuously for more than 30 seconds. Beacon information is typically control or signaling information (or both) that is broadcast either exclusively or along with other information. Broadcast beacon channels, which aid in the operation of wireless systems, may therefore be subject to FCC Rule 15.323 (c)(4), depending on the content and intended intermittency of a given beacon channel.
Due to the randomness and uncertainty of the radio environment, complying with this FCC regulation and repeating the access criteria virtually guarantees that the same channel will not be consistently selected for the wireless beacon, nor will associated mobile terminals be able to predict the beacon channel selection process. Unfortunately, mobile terminals in wireless systems need to be able to receive system information broadcasts and must therefore locate the wireless beacon that is being broadcast from the associated base station.
Mobile terminals in conventional systems scan all of the available channels to locate the wireless beacon. Disadvantageously, when a mobile terminal must search the spectrum for its associated beacon every 30 seconds, considerable battery power is expended. In other words, the scanning causes battery life to suffer significantly, which reduces both the talktime and the standby time of the mobile terminal. This excessive power expenditure applies to all mobile terminals locked to a particular hopping beacon.
In summary, existing wireless systems have required that mobile terminals waste battery power in order for the system to comply with FCC regulations. It would be advantageous if mobile terminals could locate a channel-hopping beacon without the necessity of repeatedly scanning (e.g., every 30 seconds) all of the available channels.